Archivos de biologia y medicina experimentales最新文献_第4页

Energetic metabolism and fatigability in experimental myotonia. 实验性肌强直的能量代谢和疲劳。

Archivos de biologia y medicina experimentales Pub Date : 1990-05-01

B U Ramírez

引用次数: 0

Three-dimensional morphometry of mammalian cells. II. Areas, volumes, and area-volume ratios. 哺乳动物细胞的三维形态计量学。2面积，体积和面积体积比。

Archivos de biologia y medicina experimentales Pub Date : 1990-05-01

E Morgado, C Ocqueteau, M Cury, L Becker, U González, L Muxica, B Günther

{"title":"Three-dimensional morphometry of mammalian cells. II. Areas, volumes, and area-volume ratios.","authors":"E Morgado, C Ocqueteau, M Cury, L Becker, U González, L Muxica, B Günther","doi":"","DOIUrl":"","url":null,"abstract":"From three-dimensional diameter measurements of eleven kinds of cells pertaining to five different organs, which were excised from eleven adult mammals (nine species) whose body weight range was 40 g to 450 kg, we calculated the corresponding cell soma areas (A), volumes (V), and finally their area-volume ratios (A/V). The dissimilarities among these eleven cell types could be established quantitatively by means of a cluster analysis. The dendrograms for cell areas (A), volumes (V), and their corresponding area-volume ratios (A/V), yielded similar groupings when cell areas and volumes were compared, yet the grouping of the area-volume ratios (A/V) for the eleven types of cells was different. These results were corroborated by means of the principal components analysis, where five distinct cell groupings could be established. The relationship between cellular morphometry, oxidative metabolism, and body mass, was established by means of the fractal geometry of the transport systems (respiration and circulation), which provides the tools for the scale-dependent analysis of the surfaces across which the transport of metabolites is performed.","PeriodicalId":75552,"journal":{"name":"Archivos de biologia y medicina experimentales","volume":"23 1","pages":"21-7"},"PeriodicalIF":0.0,"publicationDate":"1990-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13306542","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

On the hidden physical dimensions of the allometric equation. 异速生长方程的隐藏物理维度。

Archivos de biologia y medicina experimentales Pub Date : 1990-05-01

E Morgado, B Günther

引用次数: 0

The significance of fertilization. 施肥的重要性。

Archivos de biologia y medicina experimentales Pub Date : 1990-05-01

C R Austin

{"title":"The significance of fertilization.","authors":"C R Austin","doi":"","DOIUrl":"","url":null,"abstract":"The fertilization of a human egg, often thought of as initiating the life of a person, is in reality but the beginning of a beginning for one or more individuals. While pronuclear fusion establishes a diploid genome, this is at first a structural entity without function. No significant RNA synthesis occurs between germinal vesicle breakdown and early cleavage, and in fact embryonic genes do not begin to find expression until about the 4- to 8- cell stage. Gene expression then progressively spreads throughout the genome, during prenatal development and beyond. The progressive nature is well shown in the early mouse embryo by the widening range of energy sources utilizable, by the rising levels of glycogen storage and by the increasing uptake of nucleic acids and protein precursors. While HCG-B RNA is transcribed in human embryos about 2 days after fertilization, it is not expressed until 16-cell stage is not linked to physical or functional integration, each cell being inherently capable of giving rise to an entire person (together with a complex of placental structures); alternatively, cells from separate embryos on being brought together can jointly lead to the establishment of a chimeric individual. Multiplicity can also originate later, the primitive streak stage being the normal time for monozygotic twinning. Only when that stage has passed does true individuality exist, for (excluding anomalies) just one person can now eventuate. The gene-transfer function of fertilization can be replaced or augmented by intranuclear or intra-blastocyst gene injection, or by the use of teratocarcinoma or embryo-stem cells.","PeriodicalId":75552,"journal":{"name":"Archivos de biologia y medicina experimentales","volume":"23 1","pages":"13-5"},"PeriodicalIF":0.0,"publicationDate":"1990-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13306538","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

[Prof. Alberto Sols García]. [Alberto Sols García]教授。